Building square



FIG. 1 is an isometric view of the building square in accordance with the present design;

FIG. 2 is a top plan view in full open position of said the building square;

FIG. 3 is a top plan view in a full closed storage position of said the building square;

FIG. 4 is a top plan view showing movement of said the building square;

FIG. 5 is a top plan view showing final closure movement of said the building square; and,

FIG. 6 is a bottom plan view . This is essentially a mirror image of the top plan view shown in FIG. 1. 

The ornamental design for the building square, as shown and described. 